As an employer who sought to apply objective criteria to screen job applications I identified and began to use aptitude tests that were proven to be a reliable guide to assessing human learning ability and potential.

It proved a most productive decision. Our success in assessing potential applicants and selecting people we should employ meant that our performance retention rate was positively transformed. It is no exaggeration to say that adopting this process made as big a contribution to the success of our business as any similar decision I ever made.

The most startling benefit of an objective assessment tool for selecting job applicants was the discovery that even apparently well-qualified candidates could nevertheless lack sufficient raw intelligence, learning ability and natural aptitude to be productive employees in the demanding performance-driven manufacturing activities at Linn.

Our company’s policy is to sell by demonstration so we have to outperform the competition. To do that we need to make the best sounding, most advanced and reliable products, and all of that in turn requires the best design and manufacturing facilities and skills. The drive, aptitude, ability and imagination of employees recruited as a result of our objective selection process was to prove decisive for our success.

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An early revelation was that educational success and academic qualifications were not always an accurate guide to intelligence or aptitude, or interest in what we did, or of learning ability in general. When tested, many apparently well-qualified graduates even in challenging subjects were found to lack reasoning power. Motivation, work ethic and enthusiasm for what we do are all obviously very important, but we soon discovered that even degree level academic grades were not sufficient to qualify an applicant for successful employment. Instead we found that a broad assessment of raw intelligence and ability was a more useful guide to ability and potential than judging applicants only by their academic qualifications or past employment. Interview processes were also far less likely than chance to secure the best candidates, or reliably eliminate those who would be unable or unsuited to attain the standards we required.

Using objective testing-based screening methods and the results of subsequent real experience revealed that we needed employees with and above average, and in many roles a very high level of learning ability in general and in some instances an even higher level in a particular learning ability.

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An astonishing revelation was not only how illogical some academically highly qualified graduates were, but in contrast how many unskilled job applicants for manufacturing tasks were assessed as being in the top quartile of learning ability despite in many instances having no academic qualifications whatsoever!

How I wondered could someone, usually male and aged under thirty-five, be in the top twenty percent of the population in learning ability and yet have had no academic success whatsoever, often with not even a single ‘O’ level pass? Clearly judging people only by our education system’s results was worse than chance, and was definitely not a reliable guide to learning potential. This ability testing process also revealed that many graduates were incapable of serious logical thinking which is almost as surprising as the fact that soft degrees and those subjects that depended most on rote learning apparently attracted and favoured a high proportion of illogical thinking individuals.

The academic qualifications that attracted the least able thinkers were perhaps unsurprisingly those that depended most upon rote learning and memorising course material and where the academic tutors were equally likely to be unimaginative and impractical individuals. Indeed, academics as a group tested at the lowest levels for reasoning skills! Social scientists, lawyers and doctors are not in the main much more rational, as any experienced practitioners of ability testing will confirm. Academic career success is not typically about original thinking and reasoning abilities which are far more essential in more competitive, faster changing and more complex performance-driven, less constrained and far less predictable commercial environments.

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The supporters of Brexit have been widely derided as being low skilled, with at best average intelligence in poorly paid work, and impractical, or simply bigots who hate all foreigners! Yet this despicable and unsupportable assessment typically comes from relatively intolerant, illogical and usually privileged individuals who favour and benefit from the status quo on EU membership. The sectarian attitudes and misguided contempt expressed by some arrogant Remainers is reserved for others who do not ‘see’ how important the EU is to the ‘superior’ beneficiaries of EU largesse.

Perhaps all this explains why the higher the personal dependency on Government and centralisation of powers, the greater the enthusiasm for the EU and the more open the contempt being displayed for Brexiteers?

Could it be that in establishment centres like London and Edinburgh many of the most privileged who benefit the most from centralised big Government and the concentration of related services and business are in reality less clever, discriminating and informed than many of those they publicly despise and disparage?

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Great leaders and sound thinkers know that it makes more sense on big issues to trust the people’s vote and respect their collective democratically expressed judgement.

The self-interested majority in Parliament who with their misguided supporters and the EU-supporting media, wish to remain in the wasteful, failing and corrupt EU, will discover when it is too late that the EU will be far more damaging to our future than to have respected the will of the people who voted convincingly for Brexit.

Ivor Tiefenbrun is a Scottish manufacturer.